Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety and scope profile is covered structurally. The description adds the workspace-scoping constraint and the grounding intent, but says nothing about what a listed datastore contains (id, name, document counts) or whether the list can be long. For a zero-parameter read, this is adequate but not rich.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, zero filler, and the identification of the resource is front-loaded before the usage guidance. Every clause earns its place, including the anti-hallucination instruction about not answering from memory.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a no-argument list tool with no output schema, the description covers purpose, scope, and the natural follow-up call. It falls short only in not hinting at the shape of the returned entries, which matters slightly more because no output schema exists to explain them.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes no parameters, so there is no parameter semantics to explain and the baseline is 4. The description correctly avoids inventing filters that do not exist.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ("List all datastores") and immediately disambiguates the term with a parenthetical definition ("Business Context knowledge bases"). The workspace scope further narrows it, and the sibling datastore_query is named, so an agent can distinguish the two without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives an explicit trigger ("when the user asks about their documents, policies, or domain knowledge") and routes the agent forward with an explicit alternative ("use datastore_query to ground your answer"), including the reason to prefer it over answering from memory. Both the when and the what-next are present.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.